Container for preparing a comestible article in microwave oven, and a self-contained comestible article utilizing the same

ABSTRACT

A container ( 10 ) for preparing a comestible article in a microwave oven includes a storage chamber ( 18 ) into which a comestible article (c) cooked by exposure to microwave energy is displaced, the storage chamber ( 18 ) being characterized by the presence of a microwave shielding material ( 28 ) disposed therearound.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a container for cooking a comestible material,such as popcorn, in a microwave oven and a self-contained comestiblearticle utilizing the same.

2. Description of Related Art

Popcorn is a popular snack food that traditionally is prepared byheating a covered pan containing popping corn and an amount of edibleoil over a thermal heat source. With the advent of the microwave ovennumerous packages or methods for preparing popcorn in that device arecommercially available. Such packages typically have a measured quantityof popcorn kernels and a shortening or butter substitute, such as apartially hydrogenated edible oil, positioned on a microwave susceptormaterial. These packages are capable of cooking the majority of theinitial charge of kernels but leave a few unpopped kernels. The edibleoil provides flavoring for the popcorn similar to the flavor of meltedbutter. The edible oil conducts heat from the susceptor to the kernelsand, when melted, also acts as a microwave susceptor. Some of the edibleoil remains on the popped kernels and continues to be heated by themicrowave energy. This may cause a change in taste and actual scorchingor burning if the microwave heating continues for a sufficient time.

In view of a the foregoing it is believed advantageous to provide acontainer that serves to protect first-cooked comestibles from continuedexposure to microwave energy.

SUMMARY OF THE INVENTION

In one aspect this invention is directed to a disposable or reusablecontainer for preparing a comestible material in a microwave oven. Thecontainer includes a first portion defining a preparation chamber and asecond portion that defines a storage chamber. At least the portion ofthe container defining the preparation chamber is transparent tomicrowave energy.

In accordance with the invention the improvement comprises the storagechamber portion of the container having a microwave shielding materialdisposed therearound, such that, as a comestible material initiallydisposed within the preparation chamber is cooked by exposure tomicrowave energy the comestible material displaces from the preparationchamber into the storage chamber whereat the comestible material isshielded from further exposure to microwave energy by the microwaveshielding material.

In the disposable container embodiment the second portion is expandableto define the storage chamber. In the reusable container embodiment thepreparation chamber is removable from the storage chamber. In addition adiverter may be provided in the storage chamber.

BRIEF DESCRIPTION OF THE FIGURES

The invention will be more fully understood from the following detaileddescription taken in connection with the accompanying drawings whichform a part of this application and in which:

FIGS. 1A and 1B are side elevational views entirely in section of adisposable container for preparing a comestible material in a microwaveoven in accordance with the present invention before and after exposureof the comestible material to microwave energy, respectively;

FIGS. 2A and 2B illustrate a modified version of the disposablecontainer of FIGS. 1A, 1B before and after exposure of the comestiblematerial to microwave energy, respectively;

FIGS. 3A and 3B illustrate another modified version of the disposablecontainer of FIGS. 1A, 1B before and after exposure of the comestiblematerial to microwave energy, respectively;

FIGS. 4A and 4B illustrate yet another modified version of thedisposable container of FIGS. 1A, 1B before and after exposure of thecomestible material to microwave energy, respectively, while FIG. 4Cillustrates an alternative modification;

FIGS. 5A and 6A are side elevational views entirely in section ofanother modified embodiment of a disposable container in accordance withthe present invention respectively viewed along orthogonal section lines5A-5A, 6A-6A prior to the exposure of a comestible article within thecontainer to microwave energy;

FIGS. 5B and 6B views respectively corresponding to FIGS. 5A and 6Aafter exposure of a comestible article within the container to microwaveenergy; and

FIGS. 7A and 7B are side elevational views entirely in section of areusable container in accordance with the present invention before andafter exposure of the comestible material to microwave energy,respectively.

DETAILED DESCRIPTION OF THE INVENTION

Throughout the following detailed description similar referencecharacters refer to similar elements in all figures of the drawings.

With reference to FIGS. 1A and 1B shown is a disposable containergenerally indicated by the reference character 10 for preparing acomestible material indicated by the reference C in a microwave oven.FIG. 1A illustrates the container 10 in its on-the-shelf configurationwhile FIG. 1B illustrates the configuration of the container 10 afterexposure of the comestible material to microwave energy and prior toopening. An optional outer protective wrapping (not shown) may surroundthe container 10, if desired. In the preferred usage of the presentinvention the comestible material C is kernels of popping corn in anedible oil, such as partially hydrogenated vegetable oil.

The container 10 includes a first portion 12 and a second, expandable,portion 14. The first portion 12 defines a preparation chamber 16 inwhich the comestible material C is disposed. The comestible material Cmay be positioned on an optional layer of a microwave susceptor 20. Anysuitable susceptor 20 may be used. The susceptor sold by E. I. du Pontde Nemours and Company, Wilmington, Del., under the trademark Mylar OL®has been found suitable.

The second portion 14 of the container, when expanded, defines a storagechamber 18 (FIG. 1B) in which the cooked comestible material is held. Anoptional support base 24 may be provided on the bottom of the container10 to elevate the susceptor material 20 above the bottom wall of themicrowave oven. The support base 24 (if used) may be implemented in anyconvenient fashion such as shown by 24, 24′.

At least the first portion 12 of the container 10 is fabricated from amaterial that is substantially transparent to microwave energy. Asuitable material such as paper, paper board, or a paper board-polymerlaminate, such as a paper board-polyester terephthalate (PET)laminate,or other material having sufficient thermal stability at cookingtemperatures, may be used.

In accordance with the present invention the expandable portion 14 ofthe container 10 that forms the storage chamber 18 is fabricated from orhas a microwave shielding material 28 disposed thereon. A preferredshielding material for the expandable portion 14 is an aluminum-coatedpolyester terephthalate (PET). As shown in FIG. 1C, the aluminum coating28′ may be disposed on the exterior (or interior) of a support layer 26of the expandable portion 14. As seen in FIG. 1D, a thin sheet ofaluminum foil 28″ may alternately be used. The expandable portion 14 ofthe container 10 is folded so that in the on-the-shelf configuration(FIG. 1A) it closely overlies the preparation chamber 16 and thecomestible material C therein. The expandable portion 14 of thecontainer 10 is attached on or in the vicinity of the upper edge 12E ofthe first portion 12 using a suitable adhesive 30. A vent 14V, such as asmall hole in the expandable portion 14, may be provided to allow excesswater vapor to escape after exposure of the comestible material tomicrowave energy.

In use, the container 10 is introduced into a microwave oven and theoven is activated. As the comestible material C within the preparationchamber 16 is cooked by exposure to microwave energy it increases involume and displaces from the preparation chamber 16. The expandableportion 14 of the container 10 responds to the increase in volume anddisplacement of the cooked comestible material, indicated by thereference character C′, by unfolding to define the expandable storagechamber 18. The cooked comestible material C′ (FIG. 1B) that displacesinto the storage chamber 18 is shielded from further exposure tomicrowave energy by the microwave shielding material 28.

The container of the present invention is believed advantageous becausewithout the presence of the microwave shielding material 28 surroundingthe storage chamber 18, kernels that “pop” early in the cooking cyclewould continue to be heated by microwave energy. Without the protectionafforded by the microwave shielding material 28, continued heating wouldtend to scorch the first-“popped” kernels.

FIGS. 2A and 2B show a modified version of the disposable container 10in which the first portion 12 is extended both to enlarge thepreparation chamber 16 and to define a hollow conduit 32 that connectsthe preparation chamber 16 to the storage chamber 18. In use, theearliest-cooked kernels accumulate within the enlarged preparationchamber 16. These kernels are sequentially displaced by later-cookedkernels from the preparation chamber 16 into contact with the expandableportion 14, causing the same to enlarge to form the storage chamber 18.

Depending upon the location of the adhesive attachment 30 between theexpandable portion 14 and the first portion 12 of the container some ofthe microwave shielding material may be disposed around a region of thehollow conduit 32. This region of the conduit 32 may also affordprotection to cooked kernels from continued exposure to microwaveenergy. This relationship is made clear in FIG. 2B where the upperregion of the conduit 32 projects into the storage chamber 18. Thisprojecting portion 34 of the conduit 32 serves as a barrier that retainscomestible material cooked by exposure to microwave energy within thestorage chamber 18.

A further alternative modification to the container 10 is illustrated inFIGS. 3A and 3B. In this arrangement the projecting portion 34 of theconduit 32 is configured to prevent the entry of substantially allmicrowave energy into the storage chamber 18. In the arrangement shownthe projecting portion 34 tapers from the preparation chamber toward thestorage chamber 18.

Yet another modification to the container 10 is illustrated in FIGS. 4Aand 4B. In this arrangement a collapsible annular shelf 38 is attachedto the upper edge 32E of the conduit 32. The left hand portion of FIG.4A illustrates the shelf 38 in the collapsed configuration, while theright hand portion of that Figure illustrates the shelf 38 in theextended configuration. The expandable portion 14 of the container 10 isadhered near the perimeter of the shelf 38 by a suitable adhesive 30.The location of the attachment between the expandable portion 14 and theshelf 38 serves to enlarge the available volume of the storage chamber18 when the same is generated.

If it desired that the upper region of the conduit 32 project into thestorage chamber 18 (as in FIGS. 2B, 3B) it is necessary only to lowerthe attachment point of the shelf 38 to the conduit 32. This alternativeis illustrated by the extending portion 34 in FIG. 4C.

Yet another modification to the container 10 is illustrated in FIGS. 5Aand 6A (before exposure to microwave energy) and in FIGS. 5B and 6B(after exposure to microwave energy). In this arrangement the container10 includes a first portion 12 and a second, expandable, portion 14 inthe form of a collapsed folded bag. The first portion 12 defines apreparation chamber 16 in which the comestible material C is disposed.The comestible material C may be positioned on an optional layer of amicrowave susceptor 20. The paper support layer 26 of the expandableportion 14 has the shield material 28 coated or laminated onto theinterior (or exterior) thereof.

When exposed to microwave energy the comestible material increases involume and displaces from the preparation chamber 16 into contact withthe expandable portion 14, causing the same to enlarge to form thestorage chamber 18. A vent 14V may be provided, as discussed inconjunction with FIGS. 1A, 1B.

The present invention may also be implemented in the form of a reusablecontainer 110, as illustrated in FIGS. 7A and 7B. The reusable container110 comprises an upper portion 112 defining a preparation chamber 116and a lower portion 114 defining a storage chamber 118. The preparationchamber 116 may be connected to or supported by a support member 113.The upper portion 112 of the container defining the preparation chamber116 is transparent to microwave energy. The preparation chamber 116 maycomprise an annular recess 117 (see FIG. 7B) for receiving thecomestible material. An optional susceptor 120 may be positioned in thepreparation chamber 116.

The lower portion 114 may be constructed of a material that provides anintegral shielding function for the storage chamber 118. Alternativelythe lower portion 114 may have a shielding material 128 layered theron.On the right-hand side of FIG. 7A the shielding 128 is shown on theinside of the lower portion 114 while on the left-hand side of FIG. 7Athe shielding 128′ is shown on the outside of the lower portion 114.

A hollow conduit 124 may connect the preparation chamber 116 to thestorage chamber 118. The hollow conduit may be tapered as shown and maybe configured to attenuate microwave energy thereby to prevent the entryof substantially all the microwave energy into the storage chamber, suchas by having a layer of shielding material 128 thereon.

In operation the preparation chamber 116 receives the charge of popcornC and an edible oil (see FIG. 7A). When the comestible material Cinitially disposed within the preparation chamber 116 is cooked byexposure to microwave energy the cooked comestible material C′ (see FIG.7B) displaces from the preparation chamber into the storage chamber 118whereat the cooked comestible material C′ is shielded from furtherexposure to microwave energy by the microwave shielding material 128. Adiverter or deflector of a suitable shape 130, 130′ may be positioned todivert the cooked comestible material C′ and thus distribute it withinthe storage chamber 118.

1. A disposable container for preparing a comestible material in amicrowave oven, comprising: a first portion of the container defining apreparation chamber, a second portion of the container expandable todefine a storage chamber, at least the portion of the container definingthe preparation chamber being transparent to microwave energy, whereinthe improvement comprises: the storage chamber portion of the containerhas a microwave shielding material disposed therearound, such that, as acomestible material initially disposed within the preparation chamber iscooked by exposure to microwave energy the comestible material displacesfrom the preparation chamber into the storage chamber whereat thecomestible material is shielded from further exposure to microwaveenergy by the microwave shielding material.
 2. The disposable containerof claim 1, wherein the portion of the container defining the storagechamber is expandable as a comestible material cooked by exposure tomicrowave energy displaces thereinto.
 3. The disposable container ofclaim 1 further comprising a hollow conduit able to connect thepreparation chamber to the storage chamber.
 4. The disposable containerof claim 3 wherein the conduit projects into the storage chamber suchthat the projecting portion of the conduit serves as a barrier thatretains comestible material cooked by exposure to microwave energywithin the storage chamber.
 5. The disposable container of claim 3wherein the conduit has a microwave shielding material disposedtherearound.
 6. The disposable container of claim 5 wherein the conduitis configured to prevent the entry of substantially all microwave energyinto the storage chamber.
 7. The disposable container of claim 6 whereinthe conduit tapers from the preparation chamber toward to the storagechamber.
 8. The disposable container of claim 1 further comprising asupport base connected to the portion of the container defining thepreparation chamber.
 9. The disposable container of claim 1 wherein thecomestible material is popcorn and wherein the microwave energy causesthe popcorn to expand rapidly and thereby to displace from thepreparation chamber into the storage chamber.
 10. A reusable containerfor preparing a comestible material in a microwave oven, a first portionof the container defining a preparation chamber, a second portion of thecontainer defining a storage chamber, at least the portion of thecontainer defining the preparation chamber being transparent tomicrowave energy, wherein the improvement comprises: the storage chamberportion of the container has a microwave shielding material disposedtherearound, such that, as a comestible material initially disposedwithin the preparation chamber is cooked by exposure to microwave energythe comestible material displaces from the preparation chamber into thestorage chamber whereat the comestible material is shielded from furtherexposure to microwave energy by the microwave shielding material. 11.The reusable container of claim 10 further comprising a hollow conduitable to connect the preparation chamber to the storage chamber.
 12. Thereusable container of claim 11 wherein the conduit has a microwaveshielding material disposed therearound.
 13. The reusable container ofclaim 11 wherein the conduit is configured to attenuate microwave energythereby to prevent substantially the entry of microwave energy into thestorage chamber.
 14. The reusable container of claim 10 furthercomprising a diverter disposed within the storage chamber operative todivert comestible material displaced into the storage chamber.
 15. Thereusable container of claim 10 wherein the comestible material ispopcorn and wherein the microwave energy causes the popcorn to expandrapidly and thereby to displace from the preparation chamber into thestorage chamber.
 16. A self-contained, microwave-preparable comestiblearticle comprising: a container a first portion defining a preparationchamber and a second portion of the container expandable to define astorage chamber, the expandable portion having a microwave shieldingmaterial; and a comestible material disposed in the preparation chamber,such that, as a comestible material is cooked by exposure to microwaveenergy the comestible material displaces from the preparation chamberinto the storage chamber whereat the comestible material is shieldedfrom further exposure to microwave energy by the microwave shieldingmaterial.
 17. The container of claim 16 wherein the comestible materialis popcorn and wherein the microwave energy causes the popcorn to expandrapidly and thereby to displace from the preparation chamber into thestorage chamber.